package com.zb.util.servlet;

import java.io.File;
import java.io.IOException;
import java.text.SimpleDateFormat;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.Collections;
import java.util.Comparator;
import java.util.Hashtable;
import java.util.List;

import javax.servlet.ServletException;
import javax.servlet.annotation.WebServlet;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

import org.json.simple.JSONObject;

@WebServlet("/FileManagerJsonServlet")
public class FileManagerJsonServlet extends HttpServlet {
    private static final long serialVersionUID = 1L;

    public FileManagerJsonServlet() {
        super();
    }

    @SuppressWarnings({ "rawtypes", "unchecked" })
    protected void doGet(HttpServletRequest request,
            HttpServletResponse response) throws ServletException, IOException {
        // 根目录路径，可以指定绝对路径，比如 /var/www/attached/
        String rootPath = request.getServletContext().getRealPath("/") + "/resources/attached/";
        System.out.println("rootPath:" + rootPath);
        // 根目录URL，可以指定绝对路径，比如 http://www.yoursite.com/attached/
        String rootUrl = request.getContextPath() + "/resources/attached/";
        System.out.println("rootUrl:" + rootUrl);
        // 图片扩展名
        String[] fileTypes = new String[] { "gif", "jpg", "jpeg", "png", "bmp" };

        String dirName = request.getParameter("dir");
        if (dirName != null) {
            if (!Arrays.<String> asList(new String[] { "image", "flash", "media", "file" }).contains(dirName)) {
                response.getWriter().println("Invalid Directory name.");
                return;
            }
            rootPath += dirName + "/";
            rootUrl += dirName + "/";
            File saveDirFile = new File(rootPath);
            if (!saveDirFile.exists()) {
                saveDirFile.mkdirs();
            }
        }
        // 根据path参数，设置各路径和URL
        String path = request.getParameter("path") != null ? request.getParameter("path") : "";
        String currentPath = rootPath + path;
        String currentUrl = rootUrl + path;
        String currentDirPath = path;
        String moveupDirPath = "";
        if (!"".equals(path)) {
            String str = currentDirPath.substring(0, currentDirPath.length() - 1);
            moveupDirPath = str.lastIndexOf("/") >= 0 ? str.substring(0, str.lastIndexOf("/") + 1) : "";
        }

        // 排序形式，name or size or type
        String order = request.getParameter("order") != null ? request.getParameter("order").toLowerCase() : "name";

        // 不允许使用..移动到上一级目录
        if (path.indexOf("..") >= 0) {
            response.getWriter().println("Access is not allowed.");
            return;
        }
        // 最后一个字符不是/
        if (!"".equals(path) && !path.endsWith("/")) {
            response.getWriter().println("Parameter is not valid.");
            return;
        }
        // 目录不存在或不是目录
        File currentPathFile = new File(currentPath);
        if (!currentPathFile.isDirectory()) {
            response.getWriter().println("Directory does not exist.");
            return;
        }

        // 遍历目录取的文件信息
        List<Hashtable> fileList = new ArrayList<Hashtable>();
        if (currentPathFile.listFiles() != null) {
            for (File file : currentPathFile.listFiles()) {
                Hashtable<String, Object> hash = new Hashtable<String, Object>();
                String fileName = file.getName();
                if (file.isDirectory()) {
                    hash.put("is_dir", true);
                    hash.put("has_file", (file.listFiles() != null));
                    hash.put("filesize", 0L);
                    hash.put("is_photo", false);
                    hash.put("filetype", "");
                } else if (file.isFile()) {
                    String fileExt = fileName.substring(fileName.lastIndexOf(".") + 1).toLowerCase();
                    hash.put("is_dir", false);
                    hash.put("has_file", false);
                    hash.put("filesize", file.length());
                    hash.put("is_photo", Arrays.<String> asList(fileTypes).contains(fileExt));
                    hash.put("filetype", fileExt);
                }
                hash.put("filename", fileName);
                hash.put("datetime", new SimpleDateFormat("yyyy-MM-dd HH:mm:ss").format(file.lastModified()));
                fileList.add(hash);
            }
        }

        if ("size".equals(order)) {
            Collections.sort(fileList, new SizeComparator());
        } else if ("type".equals(order)) {
            Collections.sort(fileList, new TypeComparator());
        } else {
            Collections.sort(fileList, new NameComparator());
        }
        JSONObject result = new JSONObject();
        result.put("moveup_dir_path", moveupDirPath);
        result.put("current_dir_path", currentDirPath);
        result.put("current_url", currentUrl);
        result.put("total_count", fileList.size());
        result.put("file_list", fileList);

        response.setContentType("application/json; charset=UTF-8");
        response.getWriter().println(result.toJSONString());
    }

    @SuppressWarnings("rawtypes")
    public class NameComparator implements Comparator {
        public int compare(Object a, Object b) {
            Hashtable hashA = (Hashtable) a;
            Hashtable hashB = (Hashtable) b;
            if (((Boolean) hashA.get("is_dir")) && !((Boolean) hashB.get("is_dir"))) {
                return -1;
            } else if (!((Boolean) hashA.get("is_dir")) && ((Boolean) hashB.get("is_dir"))) {
                return 1;
            } else {
                return ((String) hashA.get("filename")).compareTo((String) hashB.get("filename"));
            }
        }
    }

    @SuppressWarnings("rawtypes")
    public class SizeComparator implements Comparator {
        public int compare(Object a, Object b) {
            Hashtable hashA = (Hashtable) a;
            Hashtable hashB = (Hashtable) b;
            if (((Boolean) hashA.get("is_dir")) && !((Boolean) hashB.get("is_dir"))) {
                return -1;
            } else if (!((Boolean) hashA.get("is_dir")) && ((Boolean) hashB.get("is_dir"))) {
                return 1;
            } else {
                if (((Long) hashA.get("filesize")) > ((Long) hashB.get("filesize"))) {
                    return 1;
                } else if (((Long) hashA.get("filesize")) < ((Long) hashB.get("filesize"))) {
                    return -1;
                } else {
                    return 0;
                }
            }
        }
    }

    @SuppressWarnings("rawtypes")
    public class TypeComparator implements Comparator {
        public int compare(Object a, Object b) {
            Hashtable hashA = (Hashtable) a;
            Hashtable hashB = (Hashtable) b;
            if (((Boolean) hashA.get("is_dir")) && !((Boolean) hashB.get("is_dir"))) {
                return -1;
            } else if (!((Boolean) hashA.get("is_dir")) && ((Boolean) hashB.get("is_dir"))) {
                return 1;
            } else {
                return ((String) hashA.get("filetype")).compareTo((String) hashB.get("filetype"));
            }
        }
    }

    protected void doPost(HttpServletRequest request,
            HttpServletResponse response) throws ServletException, IOException {
        doGet(request, response);
    }

}
